As a new discipline, the cardiac surgery has a great development in the modern age, but still faces many problems and disputes. The emergence of the evidence-based medicine(EBM),which emphasizes the best evidence, and combines the doctor’s clinical experience to make the best judgment, gives the development of the cardiac surgery a new thinking . Four systematic reviews published in The Cochrane Library (Issue 3, 2004) have interprated the importance of EBM on how to resolve the actual problems in different field of the cardiac surgery.
Objective To explore the feasibility of tissue-engineered heart valve （TEHV） reconstructed on acellularized porcine aortic valve and rabbit bone marrow stromal cells （BMSCs） in vitro. Methods Acellularized was performed in porcine aortic valve by the detergent and enzymatic extraction process . Morphological and biomechanical properties were compared between the decellularized scaffolds and the fresh valves. Rabbit BMSCs were seeded on the scaffolds. The TEHV were analyzed by light microscopy, electron microscopy and immunohistochemistry. Results Almost complete removal of the cellular components and soluble protein of valves were observed , while the construction of matrix was properly maintained. Biomechanical tests demonstrated no statistically significant change in the breaking intensity （642 ± 102 g/mm2 vs. 636 ± 127g/mm2） and breaking extensibility （62. 2%± 18. 1% vs. 54. 4%±16. 0%） in the porcine values before and after decellularization. Subsequent seeding with rabbit BMSCs on the matrix was so successful that the surface of the scaffold had been covered with a continuous monolayer cells through light microscopy and electron microscopy. Positive of α-smooth muscle actin and negative of CD31 were observed after rabbit BMSCs seeded on the matrix through immunohistochemistry. Conclusion It is feasible to reconstruct TEHV in vitro on acellularized porcine aortic valve scaffold and rabbit BMSCs.
Objective To introduce a new type of bileaflet mechanical prosthetic heart valve （GK bileaflet valve）and evaluate clinically the early hemodynamic effect and short term follow-up after its replacement. Methods Sixty-one patients with heart valve diseases were operated upon. The mitral valve replacement was performed in 34 patients, aortic valve replacement in 16 patients and double valve replacement in 11 patients. A total of 72 GK bileaflet mechanical valves were implanted, 45 in mitral position, and 27 in aortic position. Blood consistency and hemodynamics were monitored. Follow-up was carried out routinely to check whether there were some valve-related complications. Results There was no early mortality （〈30 d）. Only one patient died of trauma 2 months after the operation. Follow-up was 100% and extended 1 to 2. 5 years. Without valve-related complications all patients had lived for more than 1 to 2.5 years. In 98% （60/61） of survivors heart functional performance had improved to New York Heart Association class Ⅰ or Ⅱ . Conclusion Early clinical results and short term follow up demonstrate that GK bileaflet prosthetic heart valve exhibits excellent hemodynamic properties, satisfied blood consistency and a low incidence of valve-related complications. Midterm and long-term results should be observed further.
ObjectiveTo investigate clinical characteristics of patients with malignant cardiac tumors, and summarize our diagnostic methods and surgical treatment experience. MethodsClinical data of 16 patients with mali-gnant cardiac tumors who were admitted to Department of Cardiovascular Surgery, Second Affiliated Hospital of Harbin Medical University between January 2005 and February 2012 were retrospectively analyzed. There were 8 male and 8 female patients with their age of 35-64 (47.8±10.9) years and disease duration of 15 days to 48 months (11.8±10.9) months. Among the 16 patients, 13 patients underwent tumor resection under cardiopulmonary bypass (CPB), including 1 patient who received complete resection of the tumor and pedicle surrounding tissue and other 12 patients who only received partial tumor resection. One patient underwent concomitant tricuspid valve replacement. ResultsAll the operations were performed successfully. One patient died of low cardiac output syndrome and multiple organ dysfunction syndrome on the 6th postoperative day. All the other patients were successfully discharged. Average operation time was 181.2±59.5 minutes, average CPB time was 68.8±20.8 minutes, and average length of hospital stay was 20.4±7.4 days. Postoperative pathological examination showed primary cardiac malignant tumors in 9 patients, metastatic malignant tumors in 6 patients, and benign tumor with malignant growth in 1 patient. Three patients were followed up for a short time (≥3 months) and were still alive. Nine patients died in 1-14 months after discharge. One patient with benign cardiac tumor but malignant growth was still alive. ConclusionMalignant cardiac tumors are rare but highly malignant with a high rate of misdiagnosis. Surgical outcomes are comparatively satisfactory, but these patients' prognosis is usually poor.
The engineered heart tissues (EHTs) present a promising alternative to current materials for native myocardial tissue due to the unique characteristics. However, until now, the clinical application of EHTs is limited by a serial of practical problems yet. Generally, the challenges need to further optimize include biomaterials, cell sources, and strategies of revascularization or establishment of EHTs. This review focuses on the newly progress on these aspects to encourage the emergence of novel EHTs that can meet clinic requirement properly.